A common form of building has an interior wall of masonry construction, either poured concrete or block, and an exterior wall formed of a plurality of frame members secured to the masonry interior wall, insulation between the frame members, and sheathing overlying the insulation and frame members and secured to the latter. Typically the masonry wall is built up at least part way with the aid of inside and outside forms, and then the outer form is stripped and the frame members are secured to the outer wall surface, the insulation fitted between these members, and the sheathing secured to the frame members over the insulation.
Such style of construction therefore requires that substantial scaffolding be employed for the construction of the outer wall. Thus for a poured wall the outer form is constructed inside this scaffolding and is removed before the outer wall elements are mounted on the masonry inner wall. For a very tall building the scaffolding does not stand on the ground, but is suspended from the top of the wall or from brackets removably secured to the masonry.
The main disadvantage of this style of construction is that the assembly of the outer wall is particularly onerous. The scaffolding normally makes it fairly difficult to work on the masonry wall. Putting together the insulation, frame members, and so on through the scaffolding requires substantial time. The complexity of the job is increased by the fact that the scaffolding must be substantial enough to allow a substantial number of workers to handle and apply a large volume of materials. Thus the construction job is also fairly dangerous because much of the work must be done from scaffolding outside the structure going up.